On December 18, 2019, Marvel's Kevin Feige revealed that Season 1 of the animated series What If...? would consist of 10 episodes and that a second season of 10 episodes was already in pre-production. A few weeks later, the COVID-19 pandemic struck Hollywood, wreaking havoc on production schedules. This includes What If...? which Collider can now exclusively reveal will consist of just nine episodes — as will Season 2.

Collider spoke to executive producer Brad Winderbaum, who confirmed that the original plan called for 10 episodes before the pandemic forced Marvel brass to reassess.

"We had to push an episode into Season 2. It was just, honestly, like everything else, that was a COVID impact. There was an episode that just wouldn't hit the completion date, but luckily we do get to see it in the second season of the show," said Winderbaum, who added that "Season 2 will also be 9," thereby confirming 18 episodes in total.

Each episode of What If...? has its own pace and story rhythm, so there was no official mandate regarding running time, which gave the writers and animators a bit more creative freedom.

"We targeted a half an hour for each episode. Some of them come in a little longer, some of them come in a little shorter," said Winderbaum. "We wanted to tell as many stories as we could and we had a certain budget we had to work with so it felt like that 10-episode — now 9-episode run — was the right quantity."

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Image via Marvel Studios

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Though the show will not feature the voices of A-list stars Robert Downey Jr. (Iron Man), Chris Evans (Captain America), Tom Holland (Spider-Man), Scarlett Johansson (Black Widow), Brie Larson (Captain Marvel) or Elizabeth Olsen (Scarlet Witch), the voice cast is among the greatest ever assembled, as the star-studded ensemble includes — drumroll please...

Jaimie Alexander (Sif), Hayley Atwell (Peggy Carter), Angela Bassett (Ramonda), Paul Bettany (Vision), Leslie Bibb (Christine Everheart), Chadwick Boseman (T'Challa), Josh Brolin (Thanos), Clancy Brown (Surtur), Don Cheadle (War Machine), Carrie Coon (Proxima Midnight), Dominic Cooper (Howard Stark), Benedict Cumberbatch (Doctor Strange), David Dastmalchian (Kurt), Benicio Del Toro (The Collector), Kat Dennings (Darcy Lewis) and Michael Douglas (Hank Pym).

There's also Jon Favreau (Happy Hogan), Karen Gillan (Nebula), Jeff Goldblum (Grandmaster), Seth Green (Howard the Duck), Clark Gregg (Phil Coulson), Frank Grillo (Crossbones), Sean Gunn (Kraglin), Danai Gurira (Okoye), Chris Hemsworth (Thor), Tom Hiddleston (Loki), Djimon Hounsou (Korath the Pursuer), Rachel House (Topaz), Samuel L. Jackson (Nick Fury), Toby Jones (Arnim Zola), Michael B. Jordan (Killmonger), John Kani (T'Chaka), Evangeline Lilly (Wasp), Ophelia Lovibond (Carina), Rachel McAdams (Christine Palmer), Neal McDonough (Dum Dum Dugan) and Natalie Portman, who may very well take on the mantle of Thor on the show.

Don't forget Jeremy Renner (Hawkeye), Michael Rooker (Yondu), Paul Rudd (Ant-Man), Mark Ruffalo (Bruce Banner), Kurt Russell (Ego), Andy Serkis (Ulysses Klaue), Cobie Smulders (Maria Hill), Sebastian Stan (Bucky Barnes), Georges St-Pierre (Batroc), Chris Sullivan (Taserface), Tilda Swinton (The Ancient One), Stanley Tucci (Abraham Erskine), Emily VanCamp (Sharon Carter), Tom Vaughan-Lawlor (Ebony Maw), Taika Waititi (Korg), Bradley Whitford (John Flynn), Benedict Wong (Wong), and Jeffrey Wright (The Watcher).

That last character is of particular importance, as The Watcher is an all-powerful entity who will act as our guide to a world of endless possibilities had events in the MCU unfolded just a little bit differently. Find out just how different when Marvel's What If...? premieres on Disney+ on Wednesday, Aug. 11, and stay tuned for more from our chat with Winderbaum, who also serves as a VP of production and development at Marvel Studios.

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Image via Marvel Studios

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